How should the world respond to the threat of the islamic state?

Negotiation is the main output. They should join the countries that have been victims of this group and seek solutions through peaceful means. The above is achieved with sufficient commitment. It is a titanic task but not impossible. The largest number of nations in the world must be allied to coordinate actions of a military nature. One can also think of a diplomatic solution to the eventual failure due to possible military action.

i would think it's industries and hydroelectric power

so they can differentiate themselves from others as they saw themselves as the superior race. the star was basically a symbol that meant you are a less of a person than i am because of my race. the star was also degrading for those who had to wear it because they were aware of this and the nazis used the notion to make them feel less like a person.